Section
8: Lineage Groups and

Mountain
Hierarchies

We demonstrated that prominence, lineage areas, and domains are
non-arbitrary functions of the elevation of terrain. Lineage
Cells on the other hand are scale-specific functions.

8.1 Three Types of Parent and Three Types of
Set-Theory

Just as there is no "natural parent" of a summit there is no
perfect definition of its domain. The three types of parents can
each be applied to our understanding of lineages and areas, creating a
simple matrix of definitions.

PARENT
RELATIONSHIPS
AND GROUPS

Height-Derived

Height-Derived
plus Prominence

Height-Derived
plus Prominence
plus Proportionality

Point
(Parent)

Line Parent (NHN):Entirely scale dependent definition of parent but works
well for two reasons: Allows us to build a lineage key with a
given dataset. Always points us in the right direction across the
key saddle. Fewest constraints.

Prominence Parent (PP):Non-scale dependent definition of parent, but has some
limitation. Requires calculation of the parent prominence, which
is somewhat unrelated to the mountain in question. IE, the Parent
of Whitney requires measurement of Orizaba, not of Whitney
itself. Additional constraints.

Island Parent (IP):Non-scale dependent system works well in some cases
(measuring sub-peaks on a major mountain) but is irrelevant in other
cases (continental systems.)

Line
(Lineage)

Lineage is based on NHN rule:A line of successively higher summits all the way to the
island or continental high point. Only constraint is the scale at
which low-prominence peaks are included.

Lineage based on PP rule only:A line of successively more prominent summits.
Interesting if the notion is to identify successively greater and
greater
peaks. Robin Tivy named this the PromLine.

Lineage based on IP rule only:A matrushka doll nesting philosophy of mountains.
Gets to the continental high point pretty quickly. Limited
usefulness.

Area
(Orometric Group)

Lineage Area:The region of land that counts the summit in the
lineage. Size of area unfortunately poorly correlated to
importance of the mountain. Fewest constraints system for
building cells.

PALA or Domain:Lineage Area adjusted for Prominence. By
addition of one additional constraint, size of domain is now
well-correlated with the importance of a mountain. Some peaks can
still have huge domains depending on terrain, e.g. Pikes Peak extending
to Mississippi River.

"Prominence Island" Groupings:Not directly analogous. It is possible to draw
nested domains based on island parents. Works OK at large scales,
but becomes fairly irrelevant at the continental scale.

8.2 The Group Mentality

Having now covered the basic concepts of Lineage Theory, we can
have a little fun with the grouping of mountains into hierarchies.

The treatment of mountain hierarchies, like cladistics in taxonomy, is
a combination of rules and judgment. Strict adherence to a single
qualifying rule (such as the Prominence Island groupings above) would
yield an unsatsifactory result.

The Cell Map treatment is somewhat satisfactory at a large scale, such
as P=2,000' or greater. For my purposes, I tend to use simple
"cell-division" rules, as described in the previous section, for
mapping at P2000 or larger.

Some judgment should be employed at smaller scales in order to come up
with cells that are proportionate in size and importance. This is
because ultra-prominences are not very evenly distributed at a
continental scale. One would not ascribe the same level of
importance to a group of 2,000 sq. mi. in British Columbia as to the
entire Eastern United States, based simply on the presence of an
ultra-prominent summit.

In order to divide the world into Orometric Groups, I therefore employ
a simple three-tier system of hierarchy. This complements the
work being done by researchers at www.bivouac.com.

The first-tier is a rough division of the montane regions of the
continent. In the case of North America, this results in 17
continental divisions (plus a few groupings of islands.)

The second-tier is roughly analogous to the 5,000' prominence cutoff,
except that judgment has been used to conbine and separate regions
based on distinctive physiographic attributes. The result is that
mountainous areas are broken into regions roughly as large as a
medium-sized state.

The third-tier defaults to the simple cell structure of the
P2000s. In mountainous states, this yields a satisfactory
consistent size that allows for the classification of smaller hills by
P2000 parent. In eastern states such as West Virginia (one P2000)
or Kentucky and Pennsylvania (zero P2000s), a lower cutoff would
obviously have to be employed for the third-tier. In any respect,
it is felt that a standard prominence value suffices at this scale.

8.3 First Order
Groupings: Disecting the continent

I divided North America into 17 continental regions, as
demonstrated in the map :

In each case, the named summit is the highest point in the group.
The summit does not have to be the most prominent point in the group
(lower more prominent peaks are allowed) but in each of the North
American cases they are also most prominent.

On the map I showed the "parent" of each group summit. In this
case the parent is merely the group to which the lineage of each group
directs, it is not necessarily the PP or IP of the summit.